Tank liner

ABSTRACT

A corrosion-resistant and leakproof liner for tanks formed of flexible material and suitable for use on a variety of tanks having different sized cleanout openings. The liner has a transversely extending tubular neck portion having transverse dimensions corresponding to the transverse dimensions of the smallest standard cleanout opening of a tank of a particular size. The tubular neck portion of the liner is extended through the cleanout opening and then overlaps the flange provided on the outer end of the cleanout opening neck. When the transverse dimensions of the cleanout opening are larger than the transverse dimensions of the tubular neck portion of the liner, a lightweight support is positioned in the cleanout opening and supports the tubular neck portion of the liner to prevent collapse of the tubular neck portion of the liner and maintain a cleanout opening for the tank.

United States Patent John A. l-lendershot [72] Inventor 6508 E. 57th PL,Tulsa, Okla. 74145 [21] Appl No 803,003 [22] Filed Feb. 27, 1969 [45]Patented Nov. 30, 1971 [54] TANK LINER 7 Claims, 6 Drawing Figs.

[52] US. Cl 220/63 R [51] 865d 25/14 [50] Field of Search 220/63, 64,

[56] References Cited 1 UNITED STATES PATENTS 1,896,245 2/1933 Nagel220/63 X 2,970,042 l/l96l Lagerwey 220/63 X 3,027,286 3/1962 Kurhan....206/46 FC 3,167,209 1/1965 Jones i 220/63 3,436,324 4/1963 Hass etal.... 220/63 X 3,468,451 9/1969 Coleman 220/63 11/1969 Hansen 12/1964Suh etal.

Primary Examiner- Raphael H. Schwartz Attorney-Dunlap. Laney, Hessin &'Dougherty ing are larger than the transverse dimensions of the tubularneck portion of the liner, a lightweight support is positioned in thecleanout opening and supports the tubular neck portion of the liner toprevent collapse of the tubular neck portion of the liner and maintain acleanout opening for the tank.

1 TANK LINER 1. Field of the Invention This invention relates generallyto improvements in tanks, and more particularly to an improved linerconstmction and method of lining an existing tank.

2. Description of the Prior Art As it is well known in the art, tanksare utilized for storing a great variety of fluids, some of which arehighly corrosive. The service life of a tank will, of course, vary withthe environmental conditions. In any event, a tank will at sometimebecome corroded and develop leaks. Most tanks, particularly in the oilindustry, are relatively expensive and it has been found economical toline a corroded tank rather than to replace the tank.

A popular method of lining a tank is to apply a coating of acorrosion-resistant, plasticlike material on the internal surfaces ofthe tank. However, this method of lining requires an extensive amount ofpreparation of the tank, particularly in cleaning and treating theinternal surfaces of the tank, and results in a relatively expensiveinstallation.

It has also been known to support a flexible liner in an existing tank.However, the cleanout openings in existing tanks of the same capacityvary over a wide range, and prior to the present invention it has beenfound necessary to provide a special liner for each design of tank,making the inventory requirements for the liners prohibitive andpreventing the standardization of liner configurations with theattendant economies in manufacture of the liners.

SUMMARY OF THE INVENTION The present invention contemplates a flexibleliner for a tank of a particular rated capacity, irrespective of thesize of the cleanout opening in the tank. The flexible liner has atubular neck portion extending from one side thereof having transversedimensions corresponding to the smallest standard cleanout opening oftanks having a rated capacity for which the liner is designed. Thetubular neck portion of the liner is extended through the cleanoutopening of the tank, and in the event the transverse dimensions of thetubular neck portion of the liner are less than the transversedimensions of the cleanout opening, a lightweight support is fitted inthe cleanout opening around the neck portion of the tubular liner tosupport the intermediate portion of the tubular neck portion of theliner and retain a cleanout opening for the tank of the minimum standardsize. The neck portion of the tubular liner overlaps the flange providedaround the outer end of the cleanout opening, and the excess material inthe tubular neck portion of the liner is cut off in such a manner thatthe transverse dimensions of the free end of the tubular neck portion ofthe liner correspond with the transverse dimensions of the cleanoutopening flange. A sheet of material corresponding to the liner is alsopreferably placed over the face of the cleanout opening cover platefacing the interior of the tank to completely shield the internalsurfaces of the tank from the fluid being stored in the tank.

The present invention also contemplates a method of lining an existingtank which results in the liner construction defined in the precedingparagraph.

An object of the invention is to extend the service life of existingtanks.

Another object of the invention is to provide a corrosion resistant andleakproof liner for existing tanks, irrespective of the sizes of thecleanout openings in the tanks.

Another object of this invention is to provide a liner which may beutilized in a variety of designs of tanks of a given rated capacity.

A further object of this invention is to provide. a versatile tank linerwhich may be economically manufactured, easily installed, and which willhave a long service life.

Other objects and advantages of the invention will be evident from thefollowing detailed description when read in conjunction with theaccompanying drawing illustrating the invention.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of atypical storage tank having the present liner installed therein.

FIG. 2 is a perspective view of the liner of this invention.

FIG. 3 is a partial sectional view through an upper corner of a tankhaving the present liner installed therein as taken along lines 3-3 ofFIG. 1.

FIG. 4 is a sectional view as taken along lines 4-4 of FIG. 3.

FIG. 5 is a sectional view through the cleanout opening of a tank havingthe present liner installed therein, as taken along lines 5-5 of FIG. I.

FIG. 6 is an elevational view of a typical support to be employed in thecleanout opening of a tank when installing the present liner therein.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present liner constructionwill be described as being used with storage tanks employed in the oilindustry, although it will be understood that the liner may be employedin virtually any type of storage tank with beneficial results.

Referring to the drawings in detail, and particularly FIG. 1, referencecharacter 10 designates a typical oilfield storage tank having thepresent liner installed therein. The tank I0 is typically a cylindricaltank, having a top 12 and bottom I4, and is normally a steel tank,either welded or bolted, but may also be wooden. A cleanout opening 16is provided in one side of the tank 10 in a position to extend throughthe wall of the tank from the bottom 14. API (American PetroleumInstitute) specifications require that the cleanout opening be of arectangular configuration, but may be of various dimensions. Forexample, in a 200 barrel capacity tank, the minimum dimensions of thecleanout opening 16 are 20 inches by 24 inches, but may be larger, suchas 24 inches by 36 inches. In any event, a neck 18 normally extendsoutwardly from the side of the tank 10 around the cleanout opening 16and terminates in a mounting flange 20 on the outer end thereof. A coverplate 22 is secured to the mounting flange 20 by bolts 24 to close offthe cleanout opening 16.

The liner of this invention is illustrated in FIG. 2 in an uninstalled,but expanded disposition and is designated by the general referencecharacter 26. The liner 26 is formed of a flexible material, preferablyabout 30 mils thick, and is preferably formed of a corrosion-resistantmaterial, such as a synthetic rubber or a thermoplastic vinyl, theformulation of the material depending upon the service conditions beingencountered. The thickness of the liner 26 is exaggerated in the drawingfor clarity of illustration. The liner 26 comprises a tubular bodyportion 28 having a diameter and height substantially corresponding tothe diameter and height of a tank 10 of a particular capacity. In otherwords, the diametrical and height dimensions of liners constructed inaccordance with this invention will be standardized with respect to thediametrical and height dimensions of the tanks in which the liners areto be employed, there being a particular size of liner for each tanksize.

The bottom 30 of the liner 26 is closed to provide a protective coveringover the bottom 14 of the tank 10. The top of the body 28 of the liner26 is open and the upper edge of the body 28 is lapped or turneddownwardly and sealed to the body 28 along a line 32 to provide a hemportion 34. A plurality of circumferentially spaced openings 36 are cutin the upper edge of the hem 34 for purposes to be described.

A tubular neck portion 38, preferably of rectangular configuration incross section, extends radially outward from the side of the liner body28 adjacent the bottom 30 of the liner. The transverse dimensions of theneck portion 38 correspond to the minimum transverse dimensions of thecleanout opening which may be encountered in a standard tank of thecapacity for which the body 28 is sized. For example, for a 200 barreltank, the transverse dimensions of the neck portion 38 would be 20inches by 24 inches. The length of the tubular neck portion 38 issubstantially equal to the length of the cleanout opening neck 18 of thetank in which the liner is to be utilized. A rectangular flap 39 isformed on the outer end of the neck portion 38 and has transversedimensions greater than the transverse dimensions of the flange whichmay be encountered.

Prior to the installation of the liner 26 in the tank 10, the innersurfaces of the walls and the bottom 14 of the tank are preferablycleaned and all sharp edges on such surfaces removed. Also, a series ofholes 40 are drilled through the top 12 of the tank corresponding innumber and arrangement to the openings 36 in the hem 34 of the liner 26.

The liner 26 is then collapsed and inserted in the tank through thecleanout opening 16. A worker can then enter the tank and thread a tube42 (FIGS. 3 and 4) through the hem 34 at the upper end of the liner. Thetube 42 may be a plastic tube of any particular size or design which canbe threaded. into the hem 34 and the ends welded together to form aring. The lower end of a J-bolt 44 is then looped under the tube 42 ateach of the liner openings 36 and extended upwardly through one of theholes 40 in the top 12 of the tank. Another worker places a nut 46 oneach of the .I-bolts 44 from the exterior of the tank. The body 28 ofthe liner 26 will therefore be suspended in the tank 10.

The tubular neck portion 38 of the liner 26 is then extended through thecleanout opening 16 of the tank. In the event the transverse dimensionsof the cleanout opening 16 correspond to the transverse dimensions ofthe tubular neck portion 38, the flap 39 is simply extended radiallyoutward over the mounting flange 20 and cut off to be flush with theouter periphery of the mounting flange 20. However, as previously noted,the transverse dimensions of the cleanout opening 16 are normally largerthan the transverse dimensions of the tubular neck portion 38. In thislatter event, a support 48 is placed in the cleanout opening 16 aroundthe tubular neck portion 38 to support the tubular neck portion 38 andstill provide a cleanout opening for the tank.

Prior to installation, the support 48 has the configuration illustratedin FIG. 6. A bore or opening 50 is formed through the support 48 havingtransverse dimensions corresponding to the transverse dimensions of thetubular neck portion 38, and preferably with the comers 52 of the bore50 rounded. The overall transverse dimension, noted as A and B in FIG.6, of the support 48 correspond to the transverse dimensions of thelargest standard cleanout opening for the tank being lined. In the eventthe overall transverse dimensions, A and B, of the support 48 are largerthan the transverse dimensions of the cleanout opening 16 of the tankbeing lined, the support 48 is trimmed to the necessary extent to fitwithin the cleanout opening 16 being encountered. In a preferred form,the support 48 is made of a styrene plastic material and is easilytrimmed with a knife to fit tightly in the cleanout opening 16.

Upon installation of the support 48, the tubular neck portion 38 isextended through the opening 50 in the support 48 and then the flap 39is extended radially outward over the outer face of the support 48 andover the mounting flange 20. Any excess material remaining in the flap39 can be easily trimmed, such that the outer edge of the flap 39 willconform to the outer periphery of the mounting flange 20.

To complete the lining of the tank 10, a sheet 54 of materialcorresponding to the material employed in the liner 26 is placed overthe face of the cleanout cover 22 facing the interior of the tank It),and a spacer washer 56 is placed between the sheet 54 and thecorresponding portion of the tubular neck portion 38 in line with themounting flange 20; whereupon the cover plate 22 is secured to themounting flange 20 by the bolts 24. The tank 10 will then be lined, withall surfaces of the tank in contact with the fluid being storedprotected by a corrosion-resistant and leakproof material, and with acleanout opening still provided in the tank upon removal of the coverplate 22.

From the foregoing it will be apparent that the present invention willincrease the service life of existing tanks. The liner of this inventionmay be used on a variety of tank designs to permit the maximumstandardization and minimize inventory requirements. Installation of thelining is accomplished in a minimum of time and with a minimum ofeffort.

Changes may be made in the combination or arrangement of parts orelements, as well as the arrangement of steps or procedures, asheretofore set forth in the specification and shown in the drawingswithout departing from the spirit or scope of the invention.

What is claimed is:

1. In combination with a tank having a top and bottom, a cleanoutopening in one sidewall thereof surrounded by a neck, and a mountingflange around the outer end of the neck to mate with a cover plate forthe cleanout opening, the improvement comprising:

a liner of flexible material suspended in the tank and covering thesidewalls and bottom of the tank;

said liner having a tubular neck portion extending from a side thereofthrough the tank cleanout opening, and having a flap on the outer endthereof overlapping the mounting flange;

said tubular neck portion having transverse dimensions less than thetransverse dimensions of the cleanout opening neck;

said flap having dimensions such that it is of larger area than saidmounting flange and projects beyond said mounting flange in directionsaway from said neck;

a support positioned in the cleanout opening neck around the tubularneck portion of the liner and supporting that portion of the tubularneck portion of the liner transversing the cleanout opening neck, saidsupport being formed of an easily worked synthetic resin material forfitting in said cleanout opening snugly around said tubular neck portionof said liner; and

a sheet of corrosion-resistant material positioned over the face of thecleanout opening cover plate facing the interior of the tank andextending between the cleanout opening cover plate and the mountingflange.

2. The combination defined in claim I wherein a hem is formed around theupper end of the liner and characterized further to include a supporttube positioned in the hem, and means suspending the support tube fromthe top of the tank.

3. The combination defined in claim 1 wherein said support is formed ofstyrene plastic.

4. In combination with a tank having a top and bottom, a cleanoutopening in one sidewall thereof surrounded by a neck, and a mountingflange around the outer end of the neck to mate with a cover plate forthe cleanout opening, the improvement comprising:

a liner of flexible material in the tank open at its upper end andcovering the sidewalls and bottom of the tank, said liner having atubular neck portion extending from a side thereof through the tankcleanout opening and having a flap on the outer end thereof overlappingthe mounting flange, said tubular neck portion having transversedimensions less than than the transverse dimensions of the cleanoutopening neck, said liner also having a hem formed around the upper endthereof;

a support tube positioned in said hem;

means suspending the support tube from the top of the tank and therebysuspending the liner in the tank; and

a support positioned in the cleanout opening neck around the tubularneck portion of the liner supporting that portion of the tubular neckportion of the liner transversing the cleanout opening neck.

5. In a method of lining a tank having a top and bottom, a cleanoutopening in one sidewall thereof surrounded by a neck, and a mountingflange around the outer end of the neck to mate without a cleanoutopening cover plate, the steps of:

forming a flexible liner in a shape to cover and contact the sides andcover the bottom of the tank and have a tubular neck portion on one sidethereof with a rectangular flap on the outer end thereof and havingtransverse dimensions less than the transverse dimensions of thecleanout opening and a length substantially equal to the length of thecleanout opening neck;

suspending the liner in the tank with the tubular neck portion of theliner mating with the cleanout opening;

fitting a support in the cleanout opening neck;

forming an opening through the support conforming to the transversedimensions of the tubular neck portion of the liner;

extending the tubular neck portion of the liner through the support andthe flap radially outward over the mounting

1. In combination with a tank having a top and bottom, a cleanoutopening in one sidewall thereof surrounded by a neck, and a mountingflange around the outer end of the neck to mate with a cover plate forthe cleanout opening, the improvement comprising: a liner of flexiblematerial suspended in the tank and covering the sidewalls and bottom ofthe tank; said liner having a tubular neck portion extending from a sidethereof through the tank cleanout opening, and having a flap on theouter end thereof overlapping the mounting flange; said tubular neckportion having transverse dimensions less than the transverse dimensionsof the cleanout opening neck; said flap having dimensions such that itis of larger area than said mounting flange and projects beyond saidmounting flange in directions away from said neck; a support positionedin the cleanout opening neck around the tubular neck portion of theliner and supporting that portion of the tubular neck portion of theliner transversing the cleanout opening neck, said support being formedof an easily worked synthetic resin material for fitting in saidcleanout opening snugly around said tubular neck portion of said liner;and a sheet of corrosion-resistant material positioned over the face ofthe cleanout opening cover plate facing the interior of the tank andextending between the cleanout opening cover plate and the mountingflange.
 2. The combination defined in claim 1 wherein a hem is formedaround the upper end of the liner and characterized further to include asupport tube positioned in the hem, and meanS suspending the supporttube from the top of the tank.
 3. The combination defined in claim 1wherein said support is formed of styrene plastic.
 4. In combinationwith a tank having a top and bottom, a cleanout opening in one sidewallthereof surrounded by a neck, and a mounting flange around the outer endof the neck to mate with a cover plate for the cleanout opening, theimprovement comprising: a liner of flexible material in the tank open atits upper end and covering the sidewalls and bottom of the tank, saidliner having a tubular neck portion extending from a side thereofthrough the tank cleanout opening and having a flap on the outer endthereof overlapping the mounting flange, said tubular neck portionhaving transverse dimensions less than than the transverse dimensions ofthe cleanout opening neck, said liner also having a hem formed aroundthe upper end thereof; a support tube positioned in said hem; meanssuspending the support tube from the top of the tank and therebysuspending the liner in the tank; and a support positioned in thecleanout opening neck around the tubular neck portion of the linersupporting that portion of the tubular neck portion of the linertransversing the cleanout opening neck.
 5. In a method of lining a tankhaving a top and bottom, a cleanout opening in one sidewall thereofsurrounded by a neck, and a mounting flange around the outer end of theneck to mate without a cleanout opening cover plate, the steps of:forming a flexible liner in a shape to cover and contact the sides andcover the bottom of the tank and have a tubular neck portion on one sidethereof with a rectangular flap on the outer end thereof and havingtransverse dimensions less than the transverse dimensions of thecleanout opening and a length substantially equal to the length of thecleanout opening neck; suspending the liner in the tank with the tubularneck portion of the liner mating with the cleanout opening; fitting asupport in the cleanout opening neck; forming an opening through thesupport conforming to the transverse dimensions of the tubular neckportion of the liner; extending the tubular neck portion of the linerthrough the support and the flap radially outward over the mountingflange; cutting off that portion of the flap of the liner extendingradially beyond the mounting flange; securing the cleanout opening coverplate to the mounting flange over that portion of the tubular neckportion of the liner overlapping the mounting flange.
 6. The methoddefined in claim 5 wherein the liner is formed about 30 mils thick. 7.The method defined in claim 5 wherein the support is formed of styreneplastic.